1. Field
The following description relates to a communication network device, and in particular, to an automatic wavelength recognition apparatus and method.
2. Description of the Related Art
To smoothly handle a lot of wired traffic caused by an exponential increase of contents (including images, data and sound) and the use of various applications since the release of smartphones, high bandwidth is required for each subscriber. Conventional networks have limited transmission capacity and degraded transmission quality. To solve these problems, various forms of wavelength-division-multiplexed passive optical network (WDM-PON) architectures have been suggested. A WDM-PON provides high bandwidth by physically connecting a central office (or telephone office) and each subscriber on a point-to-point basis. However, since a single wavelength should be allocated to each subscriber, a light source used should be wavelength-independent and inexpensive. An ideal light source that meets the above requirements and can be used in transmitters of an optical network unit (ONU) and an optical line terminal (OLT) is a wavelength tunable light source that can vary a wavelength allocated to each subscriber.
However, when a wavelength tunable light source is used in a conventional ONU and a conventional OLT, since a wavelength corresponding to each channel (or port) to which the wavelength tunable light source is to be connected cannot be identified, it is difficult to recognize a wavelength of a channel in which the wavelength tunable light source is to be installed and initialize a wavelength of the wavelength tunable light source. Therefore, an installation engineer has to visit a subscriber's place, carrying a wavelength measurement device for recognizing or determining a wavelength corresponding to a channel (or port) at an installation position. In addition, the installation engineer has to manually input a value corresponding to an initial installation wavelength.
In Korean Patent Publication No. 10-2006-0065415, entitled “System and Method for Monitoring and Controlling the Optical Characteristics of the Optical Transceiver in WDM-PONs,” a network that can implement a simple network management protocol (SNMP) trap service is constructed for wavelength initialization. However, the construction of the network may incur high costs.